package com.baoteng.rbspy.open;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.List;
import java.util.Map;

import org.json.JSONObject;

public class BaiduOAuthToken {

	/**
    * 获取权限token
    * @return 返回示例：
    * {
    * "access_token": "24.460da4889caad24cccdb1fea17221975.2592000.1491995545.282335-1234567",
    * "expires_in": 2592000 30天 秒为单位
    * }
    */
   public static String getAuth() {
       String clientId = "kMvOrQ01BcSsGgELjLjA9zxC";
       String clientSecret = "tUNI6WMBagSGV1LUpNYKfXjZHjk7HPh8";
       return getAuth(clientId, clientSecret);
   }

   /**
    * 获取API访问token
    * 该token有一定的有效期，需要自行管理，当失效时需重新获取.
    * @param ak - 百度云官网获取的 API Key
    * @param sk - 百度云官网获取的 Securet Key
    * @return assess_token 示例：
    * "24.460da4889caad24cccdb1fea17221975.2592000.1491995545.282335-1234567"
    */
   public static String getAuth(String ak, String sk) {
       // 获取token地址
       String authHost = "https://aip.baidubce.com/oauth/2.0/token?";
       String getAccessTokenUrl = authHost
               // 1. grant_type为固定参数
               + "grant_type=client_credentials"
               // 2. 官网获取的 API Key
               + "&client_id=" + ak
               // 3. 官网获取的 Secret Key
               + "&client_secret=" + sk;
       try {
           URL realUrl = new URL(getAccessTokenUrl);
           // 打开和URL之间的连接
           HttpURLConnection connection = (HttpURLConnection) realUrl.openConnection();
           connection.setRequestMethod("GET");
           connection.connect();
           // 获取所有响应头字段
           Map<String, List<String>> map = connection.getHeaderFields();
           // 遍历所有的响应头字段
           for (String key : map.keySet()) {
               System.err.println(key + "--->" + map.get(key));
           }
           // 定义 BufferedReader输入流来读取URL的响应
           BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
           String result = "";
           String line;
           while ((line = in.readLine()) != null) {
               result += line;
           }
           /**
            * 返回结果示例
            */
           System.err.println("result:" + result);
           JSONObject jsonObject = new JSONObject(result);
           String access_token = jsonObject.getString("access_token");
           return access_token;
       } catch (Exception e) {
           System.err.printf("获取token失败！");
           e.printStackTrace(System.err);
       }
       return null;
   }
}
